Much of the work done in energy research involves an analysis of the costs and benefits of energy-saving technologies and other measures from the perspective of the consumer. The economic value in particular depends on the price of energy (electricity, gas or other fuel), which varies significantly both for different types of consumers, and for different regions of the country. Ideally, to provide accurate information about the economic value of energy savings, prices should be computed directly from real tariffs as defined by utility companies. A large number of utility tariffs are now available freely over the web, but the complexity and diversity of tariff structures presents a considerable barrier to using them in practice. The goal of the Tariff Analysis Project (TAP) is to collect and archive a statistically complete sample of real utility tariffs, and build a set of database and web tools that make this information relatively easy to use in cost-benefit analysis. This report presents a detailed picture of the current TAP database structure and web interface. While TAP has been designed to handle tariffs for any kind of utility service, the focus here is on electric utilities within the United States. Electricity tariffs can be very complicated, so the database structures that have been built to accommodate them are quite flexible and can be easily generalized to other commodities.